I'm new to canning and have done a bit of googling on this topic. It seems that it depends on where you are from as each country has different standards. My understanding is that when you water bath a two piece lid the oxygen can escape, leading to a safe seal. If I use a regular jar with a regular lid, does it still allow the air to escape? Some example of some products that I plan to 'can'. Quinces poached in a sugar syrup, salsa verde etc.